Cannula for a surgical instrument

ABSTRACT

This disclosure relates to a cannula for a surgical instrument used for cutting selected tissue in a body cavity while under visual inspection. A kit containing the cannula and methods for performing surgical procedures using the cannula are also described.

FIELD

This application generally relates to medical devices. In particular,the application relates to surgical instruments and the use thereof.

BACKGROUND

Conventional surgical techniques and equipment often require a fairlylarge incision over the surgical site and spreading of the incision toallow viewing and instrument access. These techniques can require alonger period of recovery than endoscopic methods and have greaterlevels of post-operative pain due to the incision size and level ofmanipulation during the procedure.

Endoscopic and arthroscopic surgeries are minimally invasive surgicalprocedures that are performed through small incisions or natural bodyopenings. An endoscopic or arthroscopic procedure typically involves useof specialized devices and direct- or remote-control manipulation ofinstruments with indirect observation of the surgical field through anendoscope, arthroscope or similar device. Compared to open surgery,endoscopic and arthroscopic surgery is a minimally invasive surgery withless postoperative pain, early resumption of usual activities and acosmetically appealing scar. It typically results in shorter hospitalstays, or allows outpatient treatment.

In general, arthroscopy is applied to introduction of a scope into ajoint anywhere in the body. Arthroscopic surgery refers to the processof introducing of the instrument to, and performing an operation at thejoint. Endoscopy is applied to introduction of a scope into a bodycavity anywhere in the body. Endoscopic surgery refers to the process ofintroducing the instruments and performing surgery at the operationsite. Further nomenclature is designated by the anatomical structure thescope is introduced into, for example if the scope is placed in thestomach it is called Gastroscopy, in the abdomen it is Laprascopy, etc.There are places where no actual cavity exists. Here, surgeons cancreate a cavity by introducing a slotted cannula to visualize thesurroundings without soft tissue obstruction, as in endoscopic carpaltunnel and cubital tunnel.

As seen in recent outbreaks of infections in hospitals, the insufficientor improper sterilization of re-usable surgical implements, can resultin the introduction of microorganisms, including drug-resistantbacteria, into the patient, potentially resulting in severe, or evenlethal, infections. This risk is magnified in procedures that requirethe insertion of multiple instruments into an incision.

The present application fulfills a need in the art for a disposablecannula attachable to endoscopic and arthroscopic surgical instrumentsuseful in uniportal procedures. Additionally, the present applicationprovides a clear cannula that allows visual observation of all tissuesaround the cannula, reducing the risk dividing unintended structures.

SUMMARY

One aspect of the present invention relates to a cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection. The cannula comprises a hollow central lumenextending from its proximal end to its distal end; the proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed. The cannula has a flattop surface with a lateral slot in the proximity of said distal endthrough which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface.

Another aspect of the present application relates to a cannula for asurgical instrument used for cutting selected tissue in a body cavitywhile under visual inspection. The cannula comprises a hollow centrallumen extending from its proximal end to its distal end; the proximalend being open and connectable to a surgical handpiece, allowing passageof an optical system and a cutting tool extension system into saidhollow central lumen; and said distal end being closed. The cannula iscircular in cross-section and has a lateral slot in the proximity ofsaid distal end through which a cutting blade can be extended andretracted under operation of the cutting tool extension system whilevisualizing tissue at said lateral slot with said optical system.

Another aspect of the present application relates to an instrument kitfor implementing an endoscopic or arthroscopic surgical procedure. Thekit comprises the cannula of the present application.

Another aspect of the present application relates to a method forperforming a uniportal procedure with a cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection. The cannula comprises a hollow central lumenextending from its proximal end to its distal end; the proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed. The cannula has a flattop surface with a lateral slot in the proximity of said distal endthrough which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface. The method comprising the steps of:a) establishing an entry portal; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to the target tissue; d) imaging the target tissue with theoptical system; e) performing an endoscopic operation at the targettissue; and f) withdrawing the cannula from the entry portal.

Another aspect of the present application relates to a method forperforming uniportal endoscopic carpal tunnel release with a cannula fora surgical instrument used for cutting selected tissue in a body cavitywhile under visual inspection. The cannula comprises a hollow centrallumen extending from its proximal end to its distal end; the proximalend being open and connectable to a surgical handpiece, allowing passageof an optical system and a cutting tool extension system into saidhollow central lumen; and said distal end being closed. The cannula hasa flat top surface with a lateral slot in the proximity of said distalend through which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface. The method comprising the steps of:a) establishing an entry portal proximal or distal of, and proximate to,the transverse carpal ligament; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to and under the transverse carpal ligament; d) imaging thetransverse carpal ligament and tissues surrounding the cannula with theoptical system; e) dividing the transverse carpal ligament; and f)withdrawing the cannula from the entry portal.

DETAILED DESCRIPTION

The following detailed description is presented to enable any personskilled in the art to make and use the invention. For purposes ofexplanation, specific nomenclature is set forth to provide a thoroughunderstanding of the present invention. However, it will be apparent toone skilled in the art that these specific details are not required topractice the invention. Descriptions of specific applications areprovided only as representative examples. The present invention is notintended to be limited to the embodiments shown, but is to be accordedthe widest possible scope consistent with the principles and featuresdisclosed herein.

This description is intended to be read in connection with theaccompanying drawings, which are to be considered part of the entirewritten description of this application. The drawing figures are notnecessarily to scale and certain features of the application may beshown exaggerated in scale or in somewhat schematic form in the interestof clarity and conciseness. In the description, relative terms such as“front,” “back,” “up,” “down,” “top,” “bottom,” “upper,” “lower,”“distal,” and “proximal” as well as derivatives thereof, should beconstrued to refer to the orientation as then described or as shown inthe drawing figure under discussion. These relative terms are forconvenience of description and normally are not intended to require aparticular orientation. Terms concerning attachments, coupling and thelike, such as “connected,” “mounted,” and “attached,” refer to arelationship wherein structures are secured or attached to one anothereither directly or indirectly through intervening structures, as well asboth movable or rigid attachments or relationships, unless expresslydescribed otherwise.

As used herein, the terms “horizontal” and “vertical,” and derivativesof those terms, are used in respect to their relationship to the planedefined by the slot in the cannula of the present application.“Vertical” refers to the plane that can, for example, pass through theslot of the cannula and bisect the cannula into two equal halves, while“horizontal” refers to a plane that is perpendicular to the verticalplane. The horizontal plane may be a level plane with respect to thelength of the cannula or housing of the device, or may be at an angle tothat level plane, allowing some upward or downward movement of elementsmoving along the horizontal plane with respect to the level plane.

As used herein, the term “subject” refers to an animal. In someembodiments, the animal is a mammal. In further embodiments, the mammalis a human.

As used herein, the term “entry portal” refers to a natural opening orincision in the body of a subject that provides access to a targettissue.

As used herein, the term “uniportal” refers to a procedure in which allinstruments that enter the body of the subject are introduced through asingle, i.e., the same, entry portal.

The present application provides a cannula for a surgical instrumentused for cutting selected tissue in a body cavity while under visualinspection. The surgical instrument may include a surgical handpiece,such as in the carpal tunnel release tool which is described in U.S.Pat. Nos. 4,926,770, 4,963,147, 5,089,000, 5,306,284, and 7,628,798,each of which are herein incorporated by reference.

The use of the present cannula, as attached to a surgical instrument, isexemplified in this application for, but not limited to, endoscopicsurgical division of a pulley or tunnel. Some other non-limiting usesfor the present cannula, as attached to a surgical instrument, include,for example, other divisions or partial separation of a tendon orligament, cutting, dividing, separating or making an incision inconnective tissue, muscle, cartilage, membranes, skin, other bodytissues or organs or any other use of the device that can be envisionedor carried out by the practitioner. As used herein, the term“practitioner” refers to one of skill in the art or any other user ofthe device. In some embodiments, the device can be used for a uniportalendoscopic viewing and/or surgical procedure. In other embodiments, thedevice can be used for an arthroscopic, laparoscopic, or thoracoscopicviewing and/or surgical procedure. As used herein, “laparoscopic” and“thoracoscopic” procedures fall within the scope of “endoscopic” and“arthroscopic” procedures.

Endoscopic or arthroscopic surgical procedures that can be performedwith a cannula of the present application include, but are not limitedto, carpal tunnel release, Guyon's canal (or tunnel) release, cubitaltunnel release, plantar fascia release, lateral release for patellarealignment, release of radial tunnel, release of pronatar teres,release of trigger finger, release of lacertus fibrosus, tendon release,release of the extensor tendons for lateral epicondylitis, release ofmedial epicondylitis, release of the posterior and other compartments ofthe leg, forearm fascia release for fascial compartment syndrome,release of fascial compartments in the upper or lower extremities,relieving the compression of a nerve by a ligament pulley or tunnel, andreleasing the travel of a ligament or tendon through a pulley or tunnel.Procedures that can be performed with a cannula or device of the presentapplication include endoscopic or arthroscopic surgical procedures onthe spine, such as discectomy for the treatment of degenerative discdisease, herniated discs, bulging discs, pinched nerves or sciatica.Procedures that can be performed with a cannula or device of the presentapplication also include procedures on cranial and facial tissues, aswell as fasciotomy release throughout the body. The cannula or device ofthe present application can be used for blood vessel, including vein orartery, harvesting throughout the body, for example to provide bloodvessel graft material in conjunction with a coronary bypass procedure orfor a reconstructive surgical procedure. Procedures that can beperformed with a cannula or device of the present application alsoinclude endoscopic procedures on the wrist and hand, including thepalmar and dorsal sides of the hand. Endoscopic procedures that can beperformed with a cannula or device of the present application on thehand also include the digits, including the thumb, index finger, middlefinger, ring finger and little (pinky) finger. Other examples ofendoscopic or arthroscopic procedures that can be performed with adevice of the present application include, but are not limited to,observation of internal tissues or injuries, cauterization of vessels,harvesting of tissues for ex vivo growth; obtaining biopsies; spinalsurgery; endonasal surgery; mucosal resection; removal of parasites,cysts or tumors, and foreign body retrieval. Still other examples ofendoscopic or arthroscopic surgery that can be performed with the deviceinclude, but are not limited to, procedures on or within bone, in oraround joints or the tendons associated with those joints, as well asany tissue, area or cavity of the body of a subject.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in the head of a subject. Exemplary proceduresin the head include, but are not limited to, nasal surgery, endoscopicsinus surgery, endoscopic pituitary surgery, cranial surgery, endoscopicear surgery, throat surgery, endodontic surgery and tonsils.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in the neck of a subject. Exemplary proceduresin the neck include, but are not limited to, laryngoscopic surgery,vocal cord surgery, esophageal surgery, thyroid surgery, carotid arterysurgery, and brachial plexus surgery.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in the chest of a subject. Exemplary proceduresin the chest include, but are not limited to, endoscopic mediastinalsurgery, thoracic surgery, heart surgery, esophageal surgery, and uppergastrointestinal (GI) scoping.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in a procedure of a finger, hand, foot of asubject.

In some other embodiments, the present cannula, as attached to asurgical instrument, can be used in the abdomen of a subject. Exemplaryprocedures in the abdomen include, but are not limited to, diagnosticlaparoscopy, laparoscopic gastric surgery, laparoscopic liver surgery,laparoscopic pancreatic surgery, laparoscopic nephrectomy and kidneysurgery, laparoscopic intestinal surgery, laparoscopic oophorectomy,laparoscopic hysterectomy, laparoscopic urinary bladder surgery,laparoscopic prostate surgery, laparoscopic aortic surgery, laparoscopicappendectomy, laparoscopic colon surgery, endoscopic hysterotomy,endoscopic fetal surgery, endoscopic hernia repair, and endoscopicsplenectomy.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in an upper extremity of a subject. Exemplaryprocedures in an upper extremity include, but are not limited to, ECTR,ECUTR, endoscopic pronator teres release, forearm fascial compartmentrelease, endoscopic repair of biceps tendon, endoscopic release oflateral and medial epicondylitis, endoscopic release of radial tunnelsyndrome, endoscopic surgery of the brachial plexus, endoscopicharvesting of nerve graft, arthroscopy and surgery of wrist, arthroscopyof elbow, arthroscopy and surgery of the carpometacarpal (CMC) joint,arthroscopy and surgery of shoulder, arthroscopy and surgery ofacromioclavicular (AC) joint.

In some embodiments, the present cannula, as attached to a surgicalinstrument, can be used in a lower extremity of a subject. Exemplaryprocedures in an lower extremity include, but are not limited to,femoral artery surgery, fascia lata release, knee lateral release,endoscopic peroneal nerve release, endoscopic leg fascial compartmentrelease, endoscopic release of gastrocnemius, endoscopic tarsal tunnelrelease, endoscopic release of Morton's neuroma, endoscopic release ofthe plantar fascia, arthroscopy of hip, knee and ankle, subtalar joint,and endoscopic harvesting of nerve and tendon graft.

Endoscopic or arthroscopic surgical procedures that can be performedwith a cannula of the present application, such as, but not limited to,a ligament or fascia release procedure, can be performed by approachingthe target tissue through an incision or body opening on either theproximate or distal side of the target tissue.

In some embodiments, a cannula of the present application can be usedfor plastic surgery. A cannula of the present application is useful fortissue remodeling or the excision of tissue segments, including necrotictissue.

One aspect of the present invention relates to a cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection. The cannula comprises a hollow central lumenextending from its proximal end to its distal end; the proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed. The cannula has a flattop surface with a lateral slot in the proximity of said distal endthrough which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface.

In some embodiments, the cannula is made from a clear material. In somefurther embodiments, the clear material is polycarbonate. In someembodiments, the cannula is marked with gradations showing how far thecannula had been inserted through an entry portal.

In some embodiments, the hollow central lumen has a length dimensionthat ranges from 3 to 15 centimeters.

In some embodiments, the width dimension of said flat top surface rangesfrom 0.1 to 1.5 centimeters.

In some embodiments, the distal end of the cannula is turned upwardslike an obturator.

Another aspect of the present application relates to a cannula for asurgical instrument used for cutting selected tissue in a body cavitywhile under visual inspection. The cannula comprises a hollow centrallumen extending from its proximal end to its distal end; the proximalend being open and connectable to a surgical handpiece, allowing passageof an optical system and a cutting tool extension system into saidhollow central lumen; and said distal end being closed. The cannula iscircular in cross-section and has a lateral slot in the proximity ofsaid distal end through which a cutting blade can be extended andretracted under operation of the cutting tool extension system whilevisualizing tissue at said lateral slot with said optical system.

In some embodiments, the cannula is made from a clear material. In somefurther embodiments, the clear material is polycarbonate. In someembodiments, the cannula is marked with gradations showing how far thecannula had been inserted through an entry portal.

In some embodiments, the hollow central lumen has a length dimensionwhich ranges from 3 to 15 centimeters.

In some embodiments, the width dimension of said flat top surface rangesfrom 0.1 to 1.5 centimeters.

In some embodiments, the distal end of the cannula is turned upwardslike an obturator.

In some embodiments, the cannula is removably attached to a handlecapable of storing a variety of surgical or exploratory tools andselectably deploying each of those tools individually into the cannulain concert with, or attached to, a viewing device. In some embodiments,the handle comprises a rotary switch for the selection of individualtools, or for advancing the viewing device into the cannula without atool. In some embodiments, the surgical or exploratory tools areselected from the group consisting of cutting blades, scrapers, rasps,biopsy loops and/or punches, cauteries, probes, lights and combinationsthereof. In some embodiments, the handle further comprises an innersleeve that encircles the path of the viewing device. The inner sleeveworks in concert with the rotary switch and comprises notches for thestorage of each individual tool.

An exemplary handle may be cylindrical, rectangular, oval or ellipticalin cross-section and comprised of two halves. The proximal end of thecannula is adapted to engage with a connection point on the front end ofthe handle. In some embodiments, the proximal end of the cannulacomprises depressions that engage with tabs (or pins) at the connectionpoint on the front end of the handle. As used herein, the term“depression” is understood to include, but is not limited to,depressions that do not penetrate completely through the material of thecannula, as well as holes or slots that penetrate completely through thematerial of the cannula.

The handle further includes an opening that can be located in eitherhalf of the handle. In some embodiments, the opening may span thejunction between the halves of the handle, being located partially ineach half. The opening is located adjacent to an internal revolver thatcomprises a selector switch that protrudes through the opening.

The handle further comprises an inner sleeve that encircles a guidancetube or tube assembly. In some embodiments, the handle further comprisesa slide lock. In some embodiments, the slide lock comprises notches anda tub separating the notches at its distal end that providepre-deployment resting places for surgical or exploratory tools. Theslide lock works in concert with the revolver in order to bring asurgical or exploratory tools, such as a blade or scraper, into theproper orientation for deployment into the cannula. The tube assemblyprovides a path for deploying an viewing device through the device andinto the cannula. The tube assembly also provides, at its distal end, amounting point or tube locator that the surgical or exploratory tool isrotated onto for deployment. At the proximate end of the handle, thetube assembly passes through a stabilizer ring, which mounts into, andseals, the proximate end of the handle. The tube assembly is advancedalong the deployed viewing device into the cannula, thereby deployingthe surgical or exploratory tool into the cannula.

In some embodiments, the surgical or exploratory tool, such as a blade,comprises a base that allows the tool to be secure in its pre-deploymentnotch of the slide lock. When the tool is rotated into deploymentorientation, the notch in the base engages a mounting point on thedistal end of a guidance tube or directly on the viewing device. In someembodiments, to prevent any unwanted side-to-side motion of the tool asit is deployed distally through the slot of the cannula, the tool mayfurther comprise a ridge that fills the slot side-to-side. Additionally,the engagement of the notch with the mounting point allows the tool tobe safely retracted back into the handle following usage of the tool fora surgical or exploratory procedure.

Described here is an exemplary relationship of the inner sleeve to therevolver of the device. The inner sleeve extends into the revolver andthe pre-deployment slots holding the surgical or exploratory tools arelocated inside the revolver. In an exemplary configuration, springs areattached to pins located on the revolver. The springs extend to pinsthat secure the opposite end of the springs to the inner sleeve. Thesprings auto center the revolver within the handle. Upon rotation of therevolver, the springs activate detents for either deployment of theviewing device alone or orientation of a surgical or exploratory tool indeployment configuration.

In some embodiments, the surgical or exploratory tools are parked innotches in the inner sleeve and are retained there when not deployed bya rotary clip. The handle may further incorporate a tube assembly thatpasses through the inner sleeve within the handle. The distal end of thetube assembly extends and is deployable into the cannula. The tubeassembly comprises near its distal end a tube locator that the surgicalor exploratory tool is engaged with for deployment into the cannula. Thetube assembly may further comprise, at its proximate end, a tube stopthat prevents the proximate end of the tube assembly from passingthrough the rear of the handle. The tube assembly has a longitudinalcentral lumen that accommodates the insertion of a viewing devicethrough the tube assembly and into the cannula in order to visualize thetissue surrounding said cannula and to observe the surgical procedureperformed with the surgical instrument. In some embodiments, theproximal end of the tube assembly is gripped by the practitioner orengaged to a grippable attachment to allow the tube assembly to beoperated manually for advancement or withdrawal of the tube assemblythrough the handle and cannula. In other embodiments, the proximal endof the tube assembly is engaged to an apparatus or machine for automaticor remote control of advancement or withdrawal of the tube assembly.

In some embodiments, the cannula is laterally expandable, allowing forimproved stretching or separation of tissues surrounding the cannula.

In some embodiments, the cannula may further comprise one or more wings,flanges or tabs mounted at or proximal to the proximate end of thecannula. Wings, flanges or tabs may be useful for manual manipulation ofthe cannula addition to, or in lieu of, a handle. In some embodiments,the wings, flanges or tabs may be useful for mounting an additionalsurgical instrument for a procedure or for mounting the cannula to animmobilizing platform, for example for additional stability of thesurgical instrument during a procedure in need thereof.

It is understood that the individual elements of the cannula and handleare not limited to the exact configuration described herein. Any designof particular elements of the cannula and handle that can be envisionedby one of ordinary skill in the art to perform the same function inconcert with other elements is included as part of the presentdisclosure.

Another aspect of the present application relates to a method forperforming a uniportal procedure with a cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection. The cannula comprises a hollow central lumenextending from its proximal end to its distal end; the proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed. The cannula has a flattop surface with a lateral slot in the proximity of said distal endthrough which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface. The method comprising the steps of:a) establishing an entry portal; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to the target tissue; d) imaging the target tissue with theoptical system; e) performing an endoscopic operation at the targettissue; and f) withdrawing the cannula from the entry portal.

In some embodiments, the cannula can be used on any target tissue, bone,joint or target area of the body of a subject.

In some embodiments, the procedure is a surgical operation comprisingthe steps of contacting the target tissue with a blade and dividing thetarget tissue with the blade. In some further embodiments, the surgicaloperation is carpal tunnel release and the target tissue is thetransverse carpal ligament. In other further embodiments, the surgicaloperation is trigger finger release and the target tissue is the Alpulley. In still other further embodiments, the surgical operation isfascia release.

Another aspect of the present application relates to a method forperforming uniportal endoscopic carpal tunnel release with a cannula fora surgical instrument used for cutting selected tissue in a body cavitywhile under visual inspection. The cannula comprises a hollow centrallumen extending from its proximal end to its distal end; the proximalend being open and connectable to a surgical handpiece, allowing passageof an optical system and a cutting tool extension system into saidhollow central lumen; and said distal end being closed. The cannula hasa flat top surface with a lateral slot in the proximity of said distalend through which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system. The flat top surface hasa width dimension spanning a distance from a first side to a second sideof said flat top surface. The cannula further has a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface. The method comprising the steps of:a) establishing an entry portal proximal or distal of, and proximate to,the transverse carpal ligament; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to and under the transverse carpal ligament; d) imaging thetransverse carpal ligament and tissues surrounding the cannula with theoptical system; e) dividing the transverse carpal ligament; and f)withdrawing the cannula from the entry portal. Kit

Another aspect of the present application relates to an instrument kitfor implementing an endoscopic or arthroscopic surgical procedure. Thekit comprises the cannula of the present application.

In some embodiments, the instrument kit comprises a surgical handpieceattachable to the proximal end of the cannula.

In some embodiments, the instrument kit comprises additional componentsand implements useful for endoscopic or arthroscopic procedures.

In another embodiment, the instrument kit further includes a scalpel.

In another embodiment, the instrument kit further includes at least oneretractor for holding open an entry portal.

Method for Endoscopic or Arthroscopic Surgery

Another aspect of the present application relates to a method foruniportal endoscopic or arthroscopic surgery using the present cannula,as attached to a surgical instrument. Uniportal endoscopic orarthroscopic surgery allows the practitioner to visualize a targettissue and its surrounding tissues as well as perform a surgicalprocedure through a single entry portal. In some instances, the entryportal may be a natural opening, while in other instances the entryportal is an incision. In the case of an incision, generally only asingle small incision must be made. In particular embodiments, theincision is less than or equal to about 2 cm in length. In moreparticular embodiments, the incision is less than or equal to about 1.5cm in length. In still more particular embodiments, the incision is lessthan or equal to about 1 cm in length. The single small incision allowsthe patient to recover more quickly and begin therapy and/or resumenormal activity as tolerated sooner. In some embodiments, the procedurecan be a uniportal percutaneous endoscopic surgical procedure.

The uniportal endoscopic surgical procedure described herein can be usedto implement a number of different surgical procedures including, butnot limited to, carpal tunnel release, Guyon's canal release, cubitaltunnel release, plantar fascia release, lateral release for patellarealignment, release of radial tunnel, release of pronatar teres,release of trigger finger, release of lacertus fibrosus, release of theextensor tendons for lateral epicondylitis, release of medialepicondylitis, release of the posterior and other compartments of theleg, forearm fascia release for fascial compartment syndrome, release offascial compartments in the upper or lower extremities, relieving thecompression of a nerve by a ligament pulley or tunnel, releasing thetravel of a ligament through a ligament pulley or tunnel, surgicalprocedures on the spine, such as endoscopic discectomy for the treatmentof degenerative disc disease, herniated discs, bulging discs, pinchednerves or sciatica, endoscopic procedures on cranial and facial tissues,fasciotomy release and blood vessel harvesting.

One embodiment of the present application relates to a method for aperforming a uniportal endoscopic or arthroscopic surgical procedure atarget tissue in a subject. Generally, the surgical procedure requiresthe establishment of an entry portal. In some embodiments of the presentapplication, the entry portal is established to the proximate side ofthe target tissue. In other embodiments of the present application, theentry portal is established to the distal side of the target tissue.

In some embodiments, the establishing an entry portal comprises makingan incision.

In some embodiments, following the establishment of an entry portal, thedistal end of the cannula is inserted through the portal to establish anopening in the underlying tissue between the portal and the targettissue. In some embodiments, the distal end of the cannula comprises afront edge for separating tissues.

The optical system is advanced from the surgical handpiece through theopen proximal end of the cannula and into the hollow central lumen ofthe cannula to view the target tissue and the surrounding tissues,assuring that the slot of the cannula is in proper orientation to thetarget tissue. In some embodiments, the optical system is an endoscopeor arthroscope.

In one embodiment, the surgical procedure is carpal tunnel release. In afurther embodiment, the target tissue is the transverse carpal ligament.

In another particular embodiment, the surgical procedure is triggerfinger release. In another particular embodiment, the target tissue isthe Al pulley.

The present invention is further illustrated by the following exampleswhich should not be construed as limiting. The contents of allreferences, patents and published patent applications cited throughoutthis application, as well as the Figures and Tables, are incorporatedherein by reference.

EXAMPLE 1 Uniportal Endoscopic Carpal Tunnel Release

In a patient presenting with carpal tunnel syndrome, an incision is madejust proximal or distal to the transverse carpal ligament (TCL), makingan entry portal.

The distal end of the cannula, as attached to a surgical instrument, isinserted into entry portal and the front edge of the cannula isintroduced into the incision and used to create a plane under the carpaltransverse ligament, but superficial to the median nerve, with the slotof the cannula facing the TCL. The procedure is observed with theoptical system. The optical system is moved/rotated within the cannulato observe and image the target tissue and surrounding tissues.

Following the creation of the plane, the optical system is used tovisualize the TCL. The slot of the cannula is aligned facing the TCL andpositioned so that the blade, when extended from the slot, contacts thefar margin of the TCL, i.e., the distal margin of the TCL when the entryportal was made proximal to the TCL, or the proximal margin of the TCLwhen the entry portal was made distal to the TCL.

The blade is then extended through the slot and cutting edge of theblade is moved into contact with the far margin of the TCL and the TCLis divided by withdrawing the cannula towards the entry portal, therebydrawing the cutting edge of the blade through the TCL. The blade isretracted back into the cannula when the near margin of the TCL has beenreached and severed.

The cannula is then moved back towards the far margin of the TCL and theoptical system is used to visualize the cut edges of the TCL. If strandsof the TCL remain uncut, the blade can then be extended out from theslot again to sever those strands.

The integrity of the underlying median nerve and tendons attached to thedigits are also visualized. While visualizing the nerve and tendons,release is confirmed by passive manipulation of the digits through theirrange of motion.

The cannula is withdrawn and removed from the entry portal. The cannulais detached from the surgical instrument and properly discarded asmedical waste.

The wound is closed and a soft bandage is applied. In some cases, asplint is also applied to immobilize the wrist up to a week.

The above description is for the purpose of teaching the person ofordinary skill in the art how to practice the present invention, and itis not intended to detail all those obvious modifications and variationsof it which will become apparent to the skilled worker upon reading thedescription. It is intended, however, that all such obviousmodifications and variations be included within the scope of the presentinvention, which is defined by the following claims. The claims areintended to cover the components and steps in any sequence which iseffective to meet the objectives there intended, unless the contextspecifically indicates the contrary.

What is claimed is:
 1. A cannula for a surgical instrument used forcutting selected tissue in a body cavity while under visual inspection,said cannula comprising: a hollow central lumen extending from itsproximal end to its distal end; said proximal end being open andconnectable to a surgical handpiece, allowing passage of an opticalsystem and a cutting tool extension system into said hollow centrallumen; and said distal end being closed; said cannula having a flat topsurface with a lateral slot in the proximity of said distal end throughwhich a cutting blade can be extended and retracted under operation ofthe cutting tool extension system while visualizing tissue at saidlateral slot with said optical system, said flat top surface having awidth dimension spanning a distance from a first side to a second sideof said flat top surface, and a contiguous lower surface having thelateral sides thereof connected to said first side and said second sideof said flat top surface, said lower surface being sized to permit apassage of an optical system and a cutting tool extension system betweensaid flat top surface and said lower surface, said lower surface beingcircular in cross-section, wherein the lateral sides of said lowersurface are curved such that they have a maximum width between thelateral sides that is greater than said width dimension of said flat topsurface.
 2. The cannula of claim 1, wherein said cannula is made from aclear material.
 3. The cannula of claim 2, wherein said clear materialis polycarbonate.
 4. The cannula of claim 1, wherein said hollow lengthhas a length dimension which ranges from 3 to 15 centimeters.
 5. Thecannula of claim 1, wherein said width dimension of said flat topsurface ranges from 0.1 to 1.5 centimeters.
 6. The cannula of claim 1,wherein said distal end is turned upwards like an obturator.
 7. Thecannula of claim 1, wherein said distal end of the cannula comprises afront edge for separating tissues.
 8. A cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection, said cannula comprising: a hollow central lumenextending from its proximal end to its distal end; said proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed; said cannula beingcircular in cross-section and having a lateral slot in the proximity ofsaid distal end through which a cutting blade can be extended andretracted under operation of the cutting tool extension system whilevisualizing tissue at said lateral slot with said optical system.
 9. Thecannula of claim 8, wherein said cannula is made from a clear material.10. The cannula of claim 9, wherein said clear material ispolycarbonate.
 11. The cannula of claim 8, wherein said hollow lengthhas a length dimension which ranges from 3 to 15 centimeters.
 12. Thecannula of claim 8, wherein said width dimension of said flat topsurface ranges from 0.1 to 1.5 centimeters.
 13. The cannula of claim 8,wherein said distal end is turned upwards like an obturator.
 14. Thecannula of claim 8, wherein said distal end of the cannula comprises afront edge for separating tissues.
 15. An instrument kit forimplementing an endoscopic or arthroscopic surgical procedure comprisinga cannula for a surgical instrument used for cutting selected tissue ina body cavity while under visual inspection, said cannula comprising: ahollow central lumen extending from its proximal end to its distal end;said proximal end being open and connectable to a surgical handpiece,allowing passage of an optical system and a cutting tool extensionsystem into said hollow central lumen; and said distal end being closed;said cannula having a flat top surface with a lateral slot in theproximity of said distal end through which a cutting blade can beextended and retracted under operation of the cutting tool extensionsystem while visualizing tissue at said lateral slot with said opticalsystem, said flat top surface having a width dimension spanning adistance from a first side to a second side of said flat top surface,and a contiguous lower surface having the lateral sides thereofconnected to said first side and said second side of said flat topsurface, said lower surface being sized to permit a passage of anoptical system and a cutting tool extension system between said flat topsurface and said lower surface, said lower surface being circular incross-section, wherein the lateral sides of said lower surface arecurved such that they have a maximum width between the lateral sidesthat is greater than said width dimension of said flat top surface. 16.A method for performing a uniportal procedure with a cannula for asurgical instrument used for cutting selected tissue in a body cavitywhile under visual inspection, said cannula comprising: a hollow centrallumen extending from its proximal end to its distal end; said proximalend being open and connectable to a surgical handpiece, allowing passageof an optical system and a cutting tool extension system into saidhollow central lumen; and said distal end being closed; said cannulahaving a flat top surface with a lateral slot in the proximity of saiddistal end through which a cutting blade can be extended and retractedunder operation of the cutting tool extension system while visualizingtissue at said lateral slot with said optical system, said flat topsurface having a width dimension spanning a distance from a first sideto a second side of said flat top surface, and a contiguous lowersurface having the lateral sides thereof connected to said first sideand said second side of said flat top surface, said lower surface beingsized to permit a passage of an optical system and a cutting toolextension system between said flat top surface and said lower surface,said lower surface being circular in cross-section, wherein the lateralsides of said lower surface are curved such that they have a maximumwidth between the lateral sides that is greater than said widthdimension of said flat top surface; the method comprising the steps of:a) establishing an entry portal; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to the target tissue; d) imaging the target tissue with theoptical system; e) performing an endoscopic operation at the targettissue; and f) withdrawing the cannula from the entry portal.
 17. Themethod of claim 16, wherein said device can be used on any targettissue, bone, joint or target area of the body of a subject.
 18. Themethod of claim 16, wherein said procedure is a surgical operationcomprising the steps of contacting the target tissue with a blade anddividing the target tissue with the blade.
 19. The method of claim 18,wherein said surgical operation is carpal tunnel release and the targettissue is the transverse carpal ligament.
 20. The method of claim 18,wherein said surgical operation is trigger finger release and the targettissue is the Al pulley.
 21. The method of claim 18, wherein saidsurgical operation is fascia release.
 22. A method for performinguniportal endoscopic carpal tunnel release with a cannula for a surgicalinstrument used for cutting selected tissue in a body cavity while undervisual inspection, said cannula comprising: a hollow central lumenextending from its proximal end to its distal end; said proximal endbeing open and connectable to a surgical handpiece, allowing passage ofan optical system and a cutting tool extension system into said hollowcentral lumen; and said distal end being closed; said cannula having aflat top surface with a lateral slot in the proximity of said distal endthrough which a cutting blade can be extended and retracted underoperation of the cutting tool extension system while visualizing tissueat said lateral slot with said optical system, said flat top surfacehaving a width dimension spanning a distance from a first side to asecond side of said flat top surface, and a contiguous lower surfacehaving the lateral sides thereof connected to said first side and saidsecond side of said flat top surface, said lower surface being sized topermit a passage of an optical system and a cutting tool extensionsystem between said flat top surface and said lower surface, said lowersurface being circular in cross-section, wherein the lateral sides ofsaid lower surface are curved such that they have a maximum widthbetween the lateral sides that is greater than said width dimension ofsaid flat top surface; the method comprising the steps of: a)establishing an entry portal proximal or distal of, and proximate to,the transverse carpal ligament; b) inserting the distal end of thecannula through the entry portal; c) advancing the cannula to create apassage to and under the transverse carpal ligament; d) imaging thetransverse carpal ligament and tissues surrounding the cannula with theoptical system; e) dividing the transverse carpal ligament; and f)withdrawing the cannula from the entry portal.